( 219 ) 
proper and wiffied-for Temperature; for when a Bird leaves its Northern 
Situation at the Approach of Winter, and advances Southward, he arrives at 
fome Place of an equal Degree of Heat with that of the Northern Summer from 
whence he departed, without coming near the Equinottial Line Q fo that I fee 
no Reafon at all to fuppofe they pafs from the North, acrofs the Line, to Southern 
Habitations, but I think it mod reafonable that they fhould flop when they have 
found a reding Place in a Climate of equal Temperature with that from which they 
departed; for to fuppofe they go a long Voyage acrofs the Line , into far diftant 
Southern Countries, is .only carrying them a long Journey to feek what they might 
find near at Hand. We know that the Stork, who inhabits fome of the more 
Northern Parts; of Europe in the Summer, retires in the Winter no farther than 
/Egypt, about the Mouths of the Nile, which is on this Side of the Line r But 
according to Mr. Catejbf s Opinion, fhe mud retire into fome Southern Terra Incog¬ 
nita, for we know of no Land, on the Old-World-Side of the Globe, of fo high a 
Southern Latitude as Holland lies North, which is one of the Summer Habita¬ 
tions of the Stork. There remains fomething yet more difficult to be cleared up in 
Relation to the Paffage of fome Birds; I mean feveral of the fhort-winged Water- 
Fowl, that, during the Summer Months, inhabit the Northern Iflands of Europe ; 
fuch as the Danijh ljla?ids of Farro, and Iceland , and many others farther North, 
even on the Coad of Greenland. Amongd thefe, the mod remarkable for its fhort 
Wings, is my Northern Penguin , figur’d in Elate 147 of this Work, which is a 
Bird never luppofed to be capable of any Flight at all, not even fo much as to 
free itfelf from the Water. There are feveral others with fhort Wings, and of 
fuch fhort Flight, that they cannot dy to the Places where they breed, on high 
Rocks, without making feveral Stages, by flying from one Ridge to another, and 
fo mounting at lad to their Neds and rooding Places. Amongd thefe are the 
Razor-Bill, the Gillemot, and the Coulterne'o, which fee defcribed by our Coun¬ 
tryman Willughby, in his Ornithology, P. 123, 4, 5. All thefe Birds, with fome 
others of the fame Genus, difappear in the Winter, and it is not conceivable that 
they fhould take long Flights in order to change their Situation, efpecially the 
Penguin, who certainly cannot fly at all. 
It remains now to confider what fhould become of thefe Birds, during their Abfence- 
from the Sight of the Inhabitants of thole Iflands: There mud be fome providential 
Means to preferve them unfeen, in that Part of the World where they ap¬ 
pear only in the Summer Months ; for in the Spring they are faid to appear all at 
once, in as great Numbers as if they had never been abfent. I think the mod 
rational Conje&ure, for the Manner of their hiding themfelves, and being preferved 
during the long and cold Winters of thofe Climates, is, that there are Sub-marine 
Caverns in the rocky Shores of thofe Iflands, the Mouths of which Caverns, 
though they be under Water, may lead to Hollows, fo rifing within Side as to 
afford a convenient dry Harbour, fit to preferve thefe Birds in a kind of torpid 
State during the Winter. The Sea lying before the Mouths of fuch Caverns, 
and they having a vad Depth of Mountain over them, their inward Capacity 
mud be defended from any rigid Cold, which may be a Means to preferve thefe 
Fowls ; and late in the Spring (about May ) the Time of the Appearance of thefe 
Birds, the outward Warmth of the Air, and the returning drong Sun Beams on 
